🔊(xi) add possibility to ignore error when indexing courses

Validation errors that happens on course indexing were not ignored by the
`ignore_errors` flag.
Fixing it.

src/api/core/warren/xi/indexers/moodle/etl.py

@@ -49,7 +49,14 @@ async def _extract(self) -> List[Course]:
 
     def _transform(self, raw: List[Course]) -> Iterator[ExperienceCreate]:
         """Transform courses into experiences."""
-        return (course.to_experience(base_url=self._lms.url) for course in raw)
+        for course in raw:
+            try:
+                yield course.to_experience(base_url=self._lms.url)
+            except ValidationError as err:
+                if not self._ignore_errors:
+                    raise err
+                logger.exception("Skipping invalid course %s", course.id)
+                pass
 
     async def _load(self, data: Iterator[ExperienceCreate]) -> None:
         """Load experiences into the Experience Index (XI)."""
@@ -121,6 +128,7 @@ def _transform(self, raw: List[Section]) -> Iterator[ExperienceCreate]:
                 if not self._ignore_errors:
                     raise err
                 logger.exception("Skipping invalid module %s", module.id)
+                pass
 
     async def _load(self, data: Iterator[ExperienceCreate]) -> None:
         """Load experiences into the Experience Index (XI) and create relations."""